rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=8a64/1/0x4000000000000000 softirq=190770/190771 fqs=5250 rcu: hardirqs softirqs csw/system rcu: number: 8412 0 0 rcu: cputime: 146 52343 4 ==> 52500(ms) rcu: (t=10502 jiffies g=175509 q=2112 ncpus=2) CPU: 1 UID: 0 PID: 26133 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:taprio_dequeue_tc_priority+0x182/0x750 net/sched/sch_taprio.c:792 Code: 48 c1 ed 03 48 89 54 24 20 48 c1 ea 03 48 89 54 24 58 48 89 4c 24 40 48 c1 e9 03 48 89 4c 24 70 49 83 ff 11 0f 83 58 01 00 00 89 a0 5f f8 42 0f b6 44 25 00 84 c0 0f 85 a6 02 00 00 41 8b 75 RSP: 0018:ffffc90000a08b40 EFLAGS: 00000283 RAX: ffffffff89606480 RBX: 0000000000000000 RCX: ffff888062983c80 RDX: 0000000000000100 RSI: 0000000000000010 RDI: 0000000000000009 RBP: 1ffff1100a3aee62 R08: 0000000000000000 R09: ffffffff895fbd66 R10: 0000000000000001 R11: ffffffff895315d0 R12: dffffc0000000000 R13: ffff888051d77314 R14: 0000000000000010 R15: 0000000000000002 FS: 000055556f1c6500(0000) GS:ffff888126235000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3245f7df98 CR3: 000000007d512000 CR4: 00000000003526f0 Call Trace: taprio_dequeue+0x186/0x550 net/sched/sch_taprio.c:-1 dequeue_skb net/sched/sch_generic.c:297 [inline] qdisc_restart net/sched/sch_generic.c:402 [inline] __qdisc_run+0x23f/0x1540 net/sched/sch_generic.c:420 qdisc_run+0xc5/0x290 include/net/pkt_sched.h:120 net_tx_action+0x7c9/0x980 net/core/dev.c:5774 handle_softirqs+0x286/0x870 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:check_preemption_disabled+0x12/0x120 lib/smp_processor_id.c:13 Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 de 64 27 07 <48> 89 44 24 08 65 8b 05 e6 64 27 07 65 8b 0d db 64 27 07 f7 c1 ff RSP: 0018:ffffc9001ad872b8 EFLAGS: 00000286 RAX: 294157243210da00 RBX: ffffffff8230f84a RCX: 0000000000000000 RDX: ffff888062983c80 RSI: ffffffff8bbf08c0 RDI: ffffffff8bbf0880 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8230f84a R10: dffffc0000000000 R11: fffff940002b14b1 R12: dffffc0000000000 R13: 0000000000000008 R14: 0000000000056296 R15: ffff88813fffa540 rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:751 rcu_read_lock_sched include/linux/rcupdate.h:959 [inline] pfn_valid+0xf3/0x490 include/linux/mmzone.h:2187 page_table_check_set+0x25/0x730 mm/page_table_check.c:105 page_table_check_ptes_set include/linux/page_table_check.h:76 [inline] set_ptes include/linux/pgtable.h:292 [inline] __copy_present_ptes mm/memory.c:1101 [inline] copy_present_ptes mm/memory.c:1180 [inline] copy_pte_range mm/memory.c:1303 [inline] copy_pmd_range+0x4b9b/0x7f00 mm/memory.c:1390 copy_pud_range mm/memory.c:1427 [inline] copy_p4d_range mm/memory.c:1451 [inline] copy_page_range+0xc14/0x1270 mm/memory.c:1539 dup_mmap+0xf4c/0x1b10 mm/mmap.c:1834 dup_mm kernel/fork.c:1489 [inline] copy_mm+0x13c/0x4b0 kernel/fork.c:1541 copy_process+0x1706/0x3c00 kernel/fork.c:2181 kernel_clone+0x21e/0x840 kernel/fork.c:2609 __do_sys_clone kernel/fork.c:2750 [inline] __se_sys_clone kernel/fork.c:2734 [inline] __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2734 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1987f85e93 Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffc638a8ab8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1987f85e93 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 000055556f1c67d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000927c0 R14: 000000000011037c R15: 00007ffc638a8c50 sched: DL replenish lagged too much